• Title/Summary/Keyword: thermal responses

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An Experimental Study on Individual Difference in Reaction to Mild Environment in Adult Males - On the Perspective of Sasang Constitution (온열 환경 반응에 대한 사상체질간 차이에 대한 실험적 연구)

  • Kim Seon-Ho;Lee Eun-Seon;Kim Ji-Eun;Park Kyung-Mo;Lee Ju-Youn;Choi Ho-Seon
    • The Journal of Korean Medicine
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    • v.26 no.1 s.61
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    • pp.123-133
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    • 2005
  • Objective : We investigated the sasang constitutional difference of physiological and psychological response in various thermal environmental conditions. Methods: Among 210 volunteers, 30 healthy subjects were selected through the QSCC II (a questionnaire for constitutional discrimination) and the manual examination of a specialist in sasang constitution. Subjects consisted of 10 each Soyang(少陽), Soeum(少陰), and Taeum(太陽). Experimental environments were set by six different conditions to be $23^{\circ}C,\;50\%\;RH,\;0.lm/s;\;25^{\circ}C,\;25\%\;RH,\;0.lm/s;\;25^{\circ}C,\;50\%\;RH,\;0.lm/s;\;25^{\circ}C,\;50\%\;RH,\;0.4m/s;\;25^{\circ}C,\;75\%\;RH,\;0.1m/s;\;and\;27^{\circ}C,\;50\%\;RH,\;0.1m\s$ (respectively temperature, relative humidity, and wind velocity). Skin temperature, core temperature, heart rate variability (HRV), and galvanic skin response (GSR) were measured for each subject Additionally, subjects were asked about comfort through the questionnaire. Results: From the viewpoint of external temperature sensibility, in all experimental environments, generally the Taeum type feels hotter and the Soeum feels colder than other types. In relative comfort, Soeum types were most sensitive to wind velocity change. From the viewpoint of body temperature, Taeum type was lower and Soyang was higher than other types. The measurements of HRV and GSR showed no difference between the types. Conclusion : The four sasang constitution types showed different responses to various thermal environmental conditions. Accordingly, our research could provide basic data for building the optimal thermal conditions for individuals based on sasang constitution. Consequently, it will help to build a healthy environment for everyday life.

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Lipoxygenase Inhibitors Suppressed Carrageenan-Induced Fos-Expression and Inflammatory Pain Responses in the Rat

  • Yoo, Sungjae;Han, Shanshu;Park, Young Shin;Lee, Jang-Hern;Oh, Uhtaek;Hwang, Sun Wook
    • Molecules and Cells
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    • v.27 no.4
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    • pp.417-422
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    • 2009
  • Lipoxygenase (LO) metabolites are generated in inflamed tissues. However, it is unclear whether the inhibition of the LO activity regulates the expression of c-Fos protein, a pain marker in the spinal cord. Here we used a carrageenan-induced inflammation model to examine the role of LO in the development of c-Fos expression. Intradermally injected carrageenan caused elevated number of cells exhibiting Fos-like immunoreactivity (Fos-LI) in the spinal dorsal horn, and decreased the thermal and mechanical threshold in Hargreaves and von Frey tests. Pretreatment with an inhibitor of phospholipase A2, that generates the LO substrate, prior to the carrageenan injection significantly reduced the number of Fos-(+) cells. A general LO inhibitor NDGA, a 5-LO inhibitor AA-861 and a 12-LO inhibitor baicalein also exhibited the similar effects. Moreover, the LO inhibitors suppressed carrageenan-induced thermal and mechanical hyperalgesic behaviors, which inidcates that the changes in Fos expression correlates with those in the nociceptive behaviors in the inflamed rats. LO products are endogenous TRPV1 activators and pretreatment with BCTC, a TRPV1 antagonist inhibited the thermal but not the mechanical hypersensitivity. Overall, our results from the Fos-LI and behavior tests suggest that LO products released from inflamed tissues contribute to nociception during carrageenan-induced inflammation, indicating that the LO pathway is a possible target for modulating inflammatory pain.

Inactivation of Mycobacteria by Radicals from Non-Thermal Plasma Jet

  • Lee, Chaebok;Subhadra, Bindu;Choi, Hei-Gwon;Suh, Hyun-Woo;Uhm, Han. S;Kim, Hwa-Jung
    • Journal of Microbiology and Biotechnology
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    • v.29 no.9
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    • pp.1401-1411
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    • 2019
  • Mycobacterial cell walls comprise thick and diverse lipids and glycolipids that act as a permeability barrier to antibiotics or other chemical agents. The use of OH radicals from a non-thermal plasma jet (NTPJ) for the inactivation of mycobacteria in aqueous solution was adopted as a novel approach. Addition of water vapor in a nitrogen plasma jet generated OH radicals, which converted to hydrogen peroxide ($H_2O_2$) that inactivated non-pathogenic Mycobacterium smegmatis and pathogenic Mycobacterium tuberculosis H37Rv. A stable plasma plume was obtained from a nitrogen plasma jet with 1.91 W of power, killing Escherichia coli and mycobacteria effectively, whereas addition of catalase decreased the effects of the former. Mycobacteria were more resistant than E. coli to NTPJ treatment. Plasma treatment enhanced intracellular ROS production and upregulation of genes related to ROS stress responses (thiolrelated oxidoreductases, such as SseA and DoxX, and ferric uptake regulator furA). Morphological changes of M. smegmatis and M. tuberculosis H37Rv were observed after 5 min treatment with $N_2+H_2O$ plasma, but not of pre-incubated sample with catalase. This finding indicates that the bactericidal efficacy of NTPJ is related to the toxicity of OH and $H_2O_2$ radicals in cells. Therefore, our study suggests that NTPJ treatment may effectively control pulmonary infections caused by M. tuberculosis and nontuberculous mycobacteria (NTM) such as M. avium or M. abscessus in water.

Inflammatory cytokines in midbrain periaqueductal gray contribute to diabetic induced pain hypersensitivity through phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway

  • Guo, Mochi;Jiang, Zongming;Chen, Yonghao;Wang, Fei;Wang, Zhifeng
    • The Korean Journal of Pain
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    • v.34 no.2
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    • pp.176-184
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    • 2021
  • Background: Diabetes-related neuropathic pain frequently occurs, and the underpinning mechanism remains elusive. The periaqueductal gray (PAG) exhibits descending inhibitory effects on central pain transmission. The current work aimed to examine whether inflammatory cytokines regulate mechanical allodynia and thermal hyperalgesia induced by diabetes through the phosphoinositide 3-kinase (PI3K)-mammalian target of rapamycin (mTOR) pathway in the PAG. Methods: Streptozotocin (STZ) was administered intraperitoneally to mimic allodynia and hyperalgesia evoked by diabetes in rats. Behavioral assays were carried out for determining mechanical pain and thermal hypersensitivity. Immunoblot and ELISA were performed to examine PAG protein amounts of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α), as well as their corresponding receptors in STZ rats, and the expression of PI3K/protein kinase B (Akt)/mTOR signaling effectors. Results: Increased PAG p-PI3K/p-Akt/p-mTOR protein amounts were observed in STZ-induced animals, a PI3K-mTOR pathway inhibition in the PAG attenuated neuropathic pain responses. Moreover, the PAG concentrations of IL-1β, IL-6, and TNF-α and their receptors (namely, IL-1R, IL-6R, and tumor necrosis factor receptor [TNFR] subtype TNFR1, respectively) were increased in the STZ rats. Additionally, inhibiting IL-1R, IL-6R, and TNFR1 ameliorated mechanical allodynia and thermal hyperalgesia in STZ rats, alongside the downregulation of PI3K-mTOR signaling. Conclusions: Overall, the current study suggests that upregulated proinflammatory cytokines and their receptors in the PAG activate PI3K-mTOR signaling, thereby producing a de-inhibition effect on descending pathways in modulating pain transmission, and eventually contributing to neuropathic pain.

Free vibration analysis of FG plates under thermal environment via a simple 4-unknown HSDT

  • Attia, Amina;Berrabah, Amina Tahar;Bousahla, Abdelmoumen Anis;Bourada, Fouad;Tounsi, Abdelouahed;Mahmoud, S.R.
    • Steel and Composite Structures
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    • v.41 no.6
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    • pp.899-910
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    • 2021
  • A 4-unknown shear deformation theory is applied to investigate the vibration of functionally graded plates under thermal environment. The plate is fabricated from a functionally graded material mixed of ceramic and metal with continuously varying material properties through the plate thickness. Three types of thermal loadings, uniform, linear and nonlinear temperature rises along the plate thickness are taken into account. The present theory contains four unknown functions as against five or more in other higher order shear deformation theories. The through-the-thickness distributions of transverse shear stresses of the plate are considered to vary parabolically and vanish at upper and lower surfaces. The present model does not require any problem dependent shear correction factor. Analytical solutions for the free vibration analysis are derived based on Fourier series that satisfy the boundary conditions (Navier's method). Benchmark solutions are firstly considered to evaluate the accuracy of the proposed model. Comparisons with the solutions available in literature revealed the good capabilities of the present model for the simulations of vibration responses of FG plates. Some parametric studies are carried out for the frequency analysis by varying the volume fraction profile and the temperature distribution across the plate thickness.

CSPACE for a simulation of core damage progression during severe accidents

  • Song, JinHo;Son, Dong-Gun;Bae, JunHo;Bae, Sung Won;Ha, KwangSoon;Chung, Bub-Dong;Choi, YuJung
    • Nuclear Engineering and Technology
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    • v.53 no.12
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    • pp.3990-4002
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    • 2021
  • CSPACE (Core meltdown, Safety and Performance Analysis CodE for nuclear power plants) for a simulation of severe accident progression in a Pressurized Water Reactor (PWR) is developed by coupling of verified system thermal hydraulic code of SPACE (Safety and Performance Analysis CodE for nuclear power plants) and core damage progression code of COMPASS (Core Meltdown Progression Accident Simulation Software). SPACE is responsible for the description of fluid state in nuclear system nodes, while COMPASS is responsible for the prediction of thermal and mechanical responses of core fuels and reactor vessel heat structures. New heat transfer models to each phase of the fluid, flow blockage, corium behavior in the lower head are added to COMPASS. Then, an interface module for the data transfer between two codes was developed to enable coupling. An implicit coupling scheme of wall heat transfer was applied to prevent fluid temperature oscillation. To validate the performance of newly developed code CSPACE, we analyzed typical severe accident scenarios for OPR1000 (Optimized Power Reactor 1000), which were initiated from large break loss of coolant accident, small break loss of coolant accident, and station black out accident. The results including thermal hydraulic behavior of RCS, core damage progression, hydrogen generation, corium behavior in the lower head, reactor vessel failure were reasonable and consistent. We demonstrate that CSPACE provides a good platform for the prediction of severe accident progression by detailed review of analysis results and a qualitative comparison with the results of previous MELCOR analysis.

Calcium/calmodulin-dependent protein kinase II is involved in the transmission and regulation of nociception in naïve and morphine-tolerant rat nucleus accumbens

  • Kai Wen Xi;De Duo Chen;Xin Geng;Yan Bian;Min Xin Wang;Hui Bian
    • The Korean Journal of Pain
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    • v.36 no.2
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    • pp.163-172
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    • 2023
  • Background: Synaptic plasticity contributes to nociceptive signal transmission and modulation, with calcium/calmodulin-dependent protein kinase II (CaMK II) playing a fundamental role in neural plasticity. This research was conducted to investigate the role of CaMK II in the transmission and regulation of nociceptive information within the nucleus accumbens (NAc) of naïve and morphine-tolerant rats. Methods: Randall Selitto and hot-plate tests were utilized to measure the hindpaw withdrawal latencies (HWLs) in response to noxious mechanical and thermal stimuli. To induce chronic morphine tolerance, rats received intraperitoneal morphine injection twice per day for seven days. CaMK II expression and activity were assessed using western blotting. Results: Intra-NAc microinjection of autocamtide-2-related inhibitory peptide (AIP) induced an increase in HWLs in naïve rats in response to noxious thermal and mechanical stimuli. Moreover, the expression of the phosphorylated CaMK II (p-CaMK II) was significantly decreased as determined by western blotting. Chronic intraperitoneal injection of morphine resulted in significant morphine tolerance in rats on Day 7, and an increase of p-CaMK II expression in NAc in morphine-tolerant rats was observed. Furthermore, intra-NAc administration of AIP elicited significant antinociceptive responses in morphine-tolerant rats. In addition, compared with naïve rats, AIP induced stronger thermal antinociceptive effects of the same dose in rats exhibiting morphine tolerance. Conclusions: This study shows that CaMK II in the NAc is involved in the transmission and regulation of nociception in naïve and morphine-tolerant rats.

Proposing a strategy based on body-thermal status to improve the welfare of heat-stressed and water-deprived goats (Capra hircus)

  • Emad M. Samara;Mohammed A. Al-Badwi;Khalid A. Abdoun;Ahmed A. Al-Haidary
    • Animal Bioscience
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    • v.37 no.12
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    • pp.2189-2201
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    • 2024
  • Objective: Despite the considerable body of research on the effects of heat stress coupled with water scarcity (either through restriction or deprivation) on goats, aimed at enhancing their welfare, there remains a notable gap in the literature regarding the subsequent period following water restoration, during which the cumulative impact is fully alleviated. In response to this gap, we propose a strategy grounded in the assessment of body-thermal status to improve the welfare of heat-stressed and water-deprived goats. Specifically, our strategy seeks to determine the minimally required recovery interval necessary to completely mitigate the residual effects of water deprivation endured for a duration of 72 hours. Methods: Eight healthy Aardi bucks, aged 10 months and weighing 30 kg, were subjected to three distinct stages: euhydration, dehydration, and rehydration. Each stage spanned for 72 hours except for the rehydration stage, which was left unrestricted. Various meteorological, biophysiological, and thermophysiological measurements were subsequently recorded. Results: Exposure of heat-stressed goats, as indicated by the temperature-humidity index values, to a 72 hours deprivation period resulted in noticeable (p<0.05) alterations in their biophysiological (daily feed intake, body weight, and feces water content) and thermophysiological responses (core, rectal, skin, and surface temperatures, respiratory and heart rates, internal, external, and total body-thermal gradients, heat tolerance and adaptability coefficients, heterothermial total body-heat storage, and total water conservation). Remarkably, our findings demonstrate that all assessed variables, whether measured or estimated, returned to their baseline euhydration levels within 10 days of commencing the rehydration phase. Conclusion: In order to improve the welfare of heat-stressed and 72 hours water-deprived goats, it is imperative to allow a recovery period of no less than 10 days following the restoration of water access prior to initiating any subsequent experiments involving these animals. Such experiments, addressing these critical aspects, serve to advance our understanding of goat welfare and obviously hold promise for contributing to future food security and economic viability.

The Clinical Study on the Thermal Changes and Side Effects after Bee Venom Acupuncture Therapy (봉약침(蜂藥鍼) 시술후(施術後) 체표온도(體表溫度) 변화(變化) 및 신체반응(身體反應)에 관(關)한 연구(硏究))

  • Kim, Kyong-Heon;Shin, Min-Seop;Yook, Tae-Han
    • Journal of Pharmacopuncture
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    • v.4 no.3
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    • pp.7-14
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    • 2001
  • Objective: This study was done to observe the effects on the thermal changes and side effects of Bee Venom acupuncture. The objectives are as follows; If there are remarkable local thermal changes between pre and post Bee Venom acupuncture therapy on D.I.T.I. or not. If there are those, we examine how long it' s changes are maintained, what is the adequate interval on Bee Venom acupuncture therapy, and what the reactions in a local or whole body are on that therapy. Methods: To study the local thermal changes in Bee Venom acupuncture therapy, D.I.T.I. was used. Determination of this analysis periods are pre and post-therapy(5 minutes, 1 hour, 1day,2days, 3days, 5days and 7days later). The study group was divided into two groups. One was BV group(N=19), another was NS(Normal Saline) group. The Bee Venom acupuncture was injected by 0.2ml divided into 0.05ml at the Fengmen(風門:12), Feishu(肺兪:B13), Fufen(附分:B41), Pohu(魄戶: B42) 4 points. Then, in order to analyze the clinical form, we have observed responses of 23 students whenever we checked the thermal changes of their after performing. Results: The following results were obtained. 1. In BV group, there was a significant dermatothermal difference between pre and post therapy. That difference was most remarkable in post-therapy 1 hour to lday, and was not remarkable in post-therapy 5-7days later. 2. There was no significant dermatothermal changes at NS group, but BV group had remarkable changes between operated and non operated area in post-therapy 1hour, 1day, 2days. But there was none 7 days later. 3. Among the physical reactions after Bee Venom acupuncture therapy, operated-area pain, itching, pain on moving and fatigue sign most appeared until post-therapy 3days. Itching and fatigue sign appeared until post-therapy 7days. 4. In comparison the dermatothermal changes with the physical reactions, the decrease of { CT = (Rt Temperature -Lt. Temperature) / Rt. $Temperature{\times}100$} and the disappearance of physical reactions were about the same.

A System Simulation Model of Proton Exchange Membrane Fuel Cell for Residential Power Generation for Thermal Management Study (가정용 연료전지 시스템의 열관리 해석을 위한 시스템 운전 모델 개발)

  • Yu, Sang-Seok;Lee, Young-Duk;Ahn, Kook-Young
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.1
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    • pp.19-26
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    • 2010
  • A PEMFC(proton exchange membrane fuel cell) is a good candidate for residential power generation to be coped with the shortage of fossil fuel and green house gas emission. The attractive benefit of the PEMFC is to produce electric power as well as hot water for home usage. The thermal management of PEMFC for RPG is to utilize the heat of PEMFC so that the PEMFC can be operated at its optimal efficiency. In this study, thermal management system of PEMFC stack is modeled to understand the dynamic response during load change. The thermal management system of PEMFC for RPGFC is composed of two cooling circuits, one for controling the fuel cell temperature and the other for heating up the water for home usage. The different operating strategy is applied for each cooling circuit considering the duty of those two circuits. Even though the capacity of PEMFC system (1kW) is enough to supply hot domestic water for residence, heat-up of reservior takes some hours. Therefore, in this study, time schedule of the simulation reflects the heat-up process. Dynamic responses and operating strategies of the PEMFC system are investigated during load changes.